DOKK / manpages / debian 10 / libexplain-dev / explain_eventfd_or_die.3.en
explain_eventfd_or_die(3) Library Functions Manual explain_eventfd_or_die(3)

explain_eventfd_or_die - create event notify file descriptor and report errors

#include <libexplain/eventfd.h>

int explain_eventfd_or_die(unsigned int initval, int flags);
int explain_eventfd_on_error(unsigned int initval, int flags);

The explain_eventfd_or_die function is used to call the eventfd(2) system call. On failure an explanation will be printed to stderr, obtained from the explain_eventfd(3) function, and then the process terminates by calling exit(EXIT_FAILURE).

The explain_eventfd_on_error function is used to call the eventfd(2) system call. On failure an explanation will be printed to stderr, obtained from the explain_eventfd(3) function, but still returns to the caller.

The initval, exactly as to be passed to the eventfd(2) system call.
The flags, exactly as to be passed to the eventfd(2) system call.

The explain_eventfd_or_die function only returns on success, see eventfd(2) for more information. On failure, prints an explanation and exits, it does not return.

The explain_eventfd_on_error function always returns the value return by the wrapped eventfd(2) system call.

The explain_eventfd_or_die function is intended to be used in a fashion similar to the following example:

int result = explain_eventfd_or_die(initval, flags);

eventfd(2)
create a file descriptor for event notification
explain_eventfd(3)
explain eventfd(2) errors
exit(2)
terminate the calling process

libexplain version 1.4
Copyright (C) 2009 Peter Miller